Ni nanoparticle-decorated biomass carbon for efficient electrocatalytic nitrite reduction to ammonia

Abstract

Electrocatalytic nitrite (NO₂⁻) reduction to ammonia (NH₃) can not only synthesize value-added NH₃, but also remove NO₂⁻ pollutants from the environment. However, the low efficiency of NO₂⁻-to-NH₃ conversion hinders its applications. Here, Ni nanoparticle-decorated juncus-derived biomass carbon prepared at 800 °C (Ni@JBC-800) serves as an efficient catalyst for NH₃ synthesis by selective electroreduction of NO₂⁻. This catalyst shows a remarkable NH₃ yield of 4117.3 μg h⁻¹ mg_cat.⁻¹ and a large faradaic efficiency of 83.4% in an alkaline electrolyte. The catalytic mechanism is further investigated by theoretical calculations.